\[\int ax^n\text dx\] let\[ax^n=u\]\[x=\left(\frac{u}{a}\right)^{1/n}=\frac{u^{1/n}}{a^{1/n}}\]\[\text dx=\frac{u^{1/n-1}}{na^{1/n}}\text du\] \[\int ax^n\text dx\longrightarrow\frac{1}{na^{1/n}}\int u\cdot{u^{1/n-1}}\text du\] \[=\frac{1}{na^{1/n}}\int {u^{1/n}}\text du\]\[=\frac{1}{na^{1/n}}\frac{u^{1/n+1}}{1/n+1}+c\]\[={}\frac{a^{1+n}x^{1+n}}{a^{1/n}+na^{1/n}}+c\]\[=\frac{ax^{1+n}}{1+n}+c\]
what can i do with this
integrate stuff ? for example \[\int\limits^{}3x^{2}=x^{3}+C\]
Why would you integrate \(ax^n\) like that... Just use the linearity of integrals and the "power rule".
i know right this is a one step problem , i realized this when i got the the end, is there any use you can think for all this latex?
your question is to integrate ax^n dx ?
Perhaps in recognizing terms in summing series.
pardon @mathmate ?
What I mean is, when we sum series, sometimes it is helpful to recognize terms in different forms. If each term is the integral / derivative of the terms of an expansion of a particular function, then the sum of the series is the integral/derivative of that function.
Is Suggestion which is a little vague accepted ?
@UnkleRhaukus ?
?
You are applying an holomorphic function to the variable - lets extend it to complex domain:
\[z^{\frac{1}{n}} = e^{\frac{1}{n}\log z} \]
ok , not too fast now
So NOW you are integrating on a differently-shaped domain in the complex plane - therefore you can do a lot of integrals differently - not this "naked" function alone but, for example , multiplied by some other function which looks simpler in the new representation
These geometric- holomorphic transforms are widely used in some areas of science and engineering
Look up antenna theory, Greens functions [ in many areas - wave propagation, solid state, QM, Field theory etc]
Mr champion ?
go on
That all seems consistent, but quite unnecessary.
I appologised from the start -" Suggestion which is a little vague ". I saw quite MASSIVE use of such domain transformation in some calculation in electromagnetism, and Wave propagation, and Green's functions computing generally. But it was some years ago, and I don't recall more precise area. Look up "geometric transformations of the complex plane" and Green function/antenna theory/etc
@UnkleRhaukus ghmm .....
ghhm Ghhm GHMM-MM-MM !
complexification
what about some (purely symbolic) gratification ...
im so confused
*is also confused* What is going on here? \[\int\limits ax^n dx = a \int\limits x^n dx = a \cdot \frac{x^{n+1}}{n+1} +c.\] by power rule, so what's the issue?
He showed how to compute it by a change of variables and asked whether it can be interesting/useful . I gave him the interpretation where it is used and he (good FREE lesson on human nature...) did NOT thank me...
Another good free lesson on human nature is how often you outright ask for medals and fans . . . ;-)
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